750 lines
18 KiB
C
750 lines
18 KiB
C
/* $NetBSD: tmpfs_vfsops.c,v 1.10 2005/12/11 12:24:29 christos Exp $ */
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/*-
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* SPDX-License-Identifier: BSD-2-Clause
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*
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* Copyright (c) 2005 The NetBSD Foundation, Inc.
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* All rights reserved.
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*
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* This code is derived from software contributed to The NetBSD Foundation
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* by Julio M. Merino Vidal, developed as part of Google's Summer of Code
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* 2005 program.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
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* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* Efficient memory file system.
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*
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* tmpfs is a file system that uses FreeBSD's virtual memory
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* sub-system to store file data and metadata in an efficient way.
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* This means that it does not follow the structure of an on-disk file
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* system because it simply does not need to. Instead, it uses
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* memory-specific data structures and algorithms to automatically
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* allocate and release resources.
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*/
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#include "opt_ddb.h"
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#include "opt_tmpfs.h"
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#include <sys/cdefs.h>
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/dirent.h>
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#include <sys/file.h>
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#include <sys/limits.h>
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#include <sys/lock.h>
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#include <sys/mount.h>
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#include <sys/mutex.h>
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#include <sys/proc.h>
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#include <sys/jail.h>
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#include <sys/kernel.h>
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#include <sys/rwlock.h>
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#include <sys/stat.h>
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#include <sys/sx.h>
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#include <sys/sysctl.h>
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#include <sys/vnode.h>
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#include <vm/vm.h>
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#include <vm/vm_param.h>
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#include <vm/pmap.h>
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#include <vm/vm_extern.h>
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#include <vm/vm_map.h>
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#include <vm/vm_object.h>
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#include <vm/vm_param.h>
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#include <fs/tmpfs/tmpfs.h>
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/*
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* Default permission for root node
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*/
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#define TMPFS_DEFAULT_ROOT_MODE (S_IRWXU|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH)
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static MALLOC_DEFINE(M_TMPFSMNT, "tmpfs mount", "tmpfs mount structures");
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MALLOC_DEFINE(M_TMPFSNAME, "tmpfs name", "tmpfs file names");
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static int tmpfs_mount(struct mount *);
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static int tmpfs_unmount(struct mount *, int);
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static int tmpfs_root(struct mount *, int flags, struct vnode **);
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static int tmpfs_fhtovp(struct mount *, struct fid *, int,
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struct vnode **);
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static int tmpfs_statfs(struct mount *, struct statfs *);
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static const char *tmpfs_opts[] = {
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"from", "easize", "size", "maxfilesize", "inodes", "uid", "gid", "mode",
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"export", "union", "nonc", "nomtime", "nosymfollow", "pgread", NULL
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};
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static const char *tmpfs_updateopts[] = {
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"from", "easize", "export", "nomtime", "size", "nosymfollow", NULL
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};
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static int
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tmpfs_update_mtime_lazy_filter(struct vnode *vp, void *arg)
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{
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struct vm_object *obj;
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if (vp->v_type != VREG)
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return (0);
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obj = atomic_load_ptr(&vp->v_object);
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if (obj == NULL)
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return (0);
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return (vm_object_mightbedirty_(obj));
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}
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static void
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tmpfs_update_mtime_lazy(struct mount *mp)
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{
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struct vnode *vp, *mvp;
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MNT_VNODE_FOREACH_LAZY(vp, mp, mvp, tmpfs_update_mtime_lazy_filter, NULL) {
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if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK) != 0)
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continue;
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tmpfs_check_mtime(vp);
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vput(vp);
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}
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}
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static void
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tmpfs_update_mtime_all(struct mount *mp)
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{
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struct vnode *vp, *mvp;
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if (VFS_TO_TMPFS(mp)->tm_nomtime)
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return;
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MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
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if (vp->v_type != VREG) {
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VI_UNLOCK(vp);
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continue;
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}
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if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK) != 0)
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continue;
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tmpfs_check_mtime(vp);
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tmpfs_update(vp);
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vput(vp);
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}
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}
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struct tmpfs_check_rw_maps_arg {
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bool found;
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};
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static bool
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tmpfs_check_rw_maps_cb(struct mount *mp __unused, vm_map_t map __unused,
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vm_map_entry_t entry __unused, void *arg)
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{
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struct tmpfs_check_rw_maps_arg *a;
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a = arg;
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a->found = true;
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return (true);
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}
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/*
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* Revoke write permissions from all mappings of regular files
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* belonging to the specified tmpfs mount.
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*/
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static bool
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tmpfs_revoke_rw_maps_cb(struct mount *mp __unused, vm_map_t map,
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vm_map_entry_t entry, void *arg __unused)
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{
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/*
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* XXXKIB: might be invalidate the mapping
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* instead ? The process is not going to be
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* happy in any case.
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*/
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entry->max_protection &= ~VM_PROT_WRITE;
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if ((entry->protection & VM_PROT_WRITE) != 0) {
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entry->protection &= ~VM_PROT_WRITE;
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pmap_protect(map->pmap, entry->start, entry->end,
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entry->protection);
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}
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return (false);
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}
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static void
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tmpfs_all_rw_maps(struct mount *mp, bool (*cb)(struct mount *mp, vm_map_t,
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vm_map_entry_t, void *), void *cb_arg)
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{
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struct proc *p;
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struct vmspace *vm;
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vm_map_t map;
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vm_map_entry_t entry;
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vm_object_t object;
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struct vnode *vp;
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int gen;
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bool terminate;
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terminate = false;
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sx_slock(&allproc_lock);
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again:
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gen = allproc_gen;
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FOREACH_PROC_IN_SYSTEM(p) {
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PROC_LOCK(p);
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if (p->p_state != PRS_NORMAL || (p->p_flag & (P_INEXEC |
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P_SYSTEM | P_WEXIT)) != 0) {
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PROC_UNLOCK(p);
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continue;
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}
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vm = vmspace_acquire_ref(p);
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_PHOLD_LITE(p);
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PROC_UNLOCK(p);
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if (vm == NULL) {
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PRELE(p);
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continue;
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}
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sx_sunlock(&allproc_lock);
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map = &vm->vm_map;
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vm_map_lock(map);
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if (map->busy)
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vm_map_wait_busy(map);
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VM_MAP_ENTRY_FOREACH(entry, map) {
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if ((entry->eflags & (MAP_ENTRY_GUARD |
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MAP_ENTRY_IS_SUB_MAP | MAP_ENTRY_COW)) != 0 ||
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(entry->max_protection & VM_PROT_WRITE) == 0)
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continue;
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object = entry->object.vm_object;
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if (object == NULL || object->type != tmpfs_pager_type)
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continue;
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/*
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* No need to dig into shadow chain, mapping
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* of the object not at top is readonly.
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*/
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VM_OBJECT_RLOCK(object);
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if (object->type == OBJT_DEAD) {
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VM_OBJECT_RUNLOCK(object);
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continue;
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}
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MPASS(object->ref_count > 1);
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if ((object->flags & OBJ_TMPFS) == 0) {
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VM_OBJECT_RUNLOCK(object);
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continue;
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}
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vp = VM_TO_TMPFS_VP(object);
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if (vp->v_mount != mp) {
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VM_OBJECT_RUNLOCK(object);
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continue;
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}
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terminate = cb(mp, map, entry, cb_arg);
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VM_OBJECT_RUNLOCK(object);
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if (terminate)
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break;
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}
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vm_map_unlock(map);
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vmspace_free(vm);
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sx_slock(&allproc_lock);
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PRELE(p);
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if (terminate)
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break;
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}
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if (!terminate && gen != allproc_gen)
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goto again;
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sx_sunlock(&allproc_lock);
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}
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static bool
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tmpfs_check_rw_maps(struct mount *mp)
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{
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struct tmpfs_check_rw_maps_arg ca;
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ca.found = false;
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tmpfs_all_rw_maps(mp, tmpfs_check_rw_maps_cb, &ca);
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return (ca.found);
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}
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static int
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tmpfs_rw_to_ro(struct mount *mp)
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{
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int error, flags;
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bool forced;
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forced = (mp->mnt_flag & MNT_FORCE) != 0;
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flags = WRITECLOSE | (forced ? FORCECLOSE : 0);
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if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0)
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return (error);
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error = vfs_write_suspend_umnt(mp);
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if (error != 0)
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return (error);
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if (!forced && tmpfs_check_rw_maps(mp)) {
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error = EBUSY;
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goto out;
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}
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VFS_TO_TMPFS(mp)->tm_ronly = 1;
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MNT_ILOCK(mp);
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mp->mnt_flag |= MNT_RDONLY;
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MNT_IUNLOCK(mp);
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for (;;) {
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tmpfs_all_rw_maps(mp, tmpfs_revoke_rw_maps_cb, NULL);
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tmpfs_update_mtime_all(mp);
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error = vflush(mp, 0, flags, curthread);
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if (error != 0) {
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VFS_TO_TMPFS(mp)->tm_ronly = 0;
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MNT_ILOCK(mp);
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mp->mnt_flag &= ~MNT_RDONLY;
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MNT_IUNLOCK(mp);
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goto out;
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}
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if (!tmpfs_check_rw_maps(mp))
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break;
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}
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out:
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vfs_write_resume(mp, 0);
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return (error);
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}
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static int
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tmpfs_mount(struct mount *mp)
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{
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const size_t nodes_per_page = howmany(PAGE_SIZE,
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sizeof(struct tmpfs_dirent) + sizeof(struct tmpfs_node));
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struct tmpfs_mount *tmp;
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struct tmpfs_node *root;
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int error;
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bool nomtime, nonc, pgread;
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/* Size counters. */
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u_quad_t pages;
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off_t nodes_max, size_max, maxfilesize, ea_max_size;
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/* Root node attributes. */
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uid_t root_uid;
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gid_t root_gid;
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mode_t root_mode;
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struct vattr va;
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if (vfs_filteropt(mp->mnt_optnew, tmpfs_opts))
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return (EINVAL);
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if (mp->mnt_flag & MNT_UPDATE) {
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/* Only support update mounts for certain options. */
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if (vfs_filteropt(mp->mnt_optnew, tmpfs_updateopts) != 0)
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return (EOPNOTSUPP);
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tmp = VFS_TO_TMPFS(mp);
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if (vfs_getopt_size(mp->mnt_optnew, "size", &size_max) == 0) {
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/*
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* On-the-fly resizing is not supported (yet). We still
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* need to have "size" listed as "supported", otherwise
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* trying to update fs that is listed in fstab with size
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* parameter, say trying to change rw to ro or vice
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* versa, would cause vfs_filteropt() to bail.
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*/
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if (size_max != tmp->tm_size_max)
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return (EOPNOTSUPP);
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}
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if (vfs_getopt_size(mp->mnt_optnew, "easize", &ea_max_size) == 0) {
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tmp->tm_ea_memory_max = ea_max_size;
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}
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if (vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0) &&
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!tmp->tm_ronly) {
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/* RW -> RO */
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return (tmpfs_rw_to_ro(mp));
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} else if (!vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0) &&
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tmp->tm_ronly) {
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/* RO -> RW */
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tmp->tm_ronly = 0;
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MNT_ILOCK(mp);
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mp->mnt_flag &= ~MNT_RDONLY;
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MNT_IUNLOCK(mp);
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}
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tmp->tm_nomtime = vfs_getopt(mp->mnt_optnew, "nomtime", NULL,
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0) == 0;
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MNT_ILOCK(mp);
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if ((mp->mnt_flag & MNT_UNION) == 0) {
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mp->mnt_kern_flag |= MNTK_FPLOOKUP;
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} else {
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mp->mnt_kern_flag &= ~MNTK_FPLOOKUP;
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}
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MNT_IUNLOCK(mp);
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return (0);
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}
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vn_lock(mp->mnt_vnodecovered, LK_SHARED | LK_RETRY);
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error = VOP_GETATTR(mp->mnt_vnodecovered, &va, mp->mnt_cred);
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VOP_UNLOCK(mp->mnt_vnodecovered);
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if (error)
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return (error);
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if (mp->mnt_cred->cr_ruid != 0 ||
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vfs_scanopt(mp->mnt_optnew, "gid", "%d", &root_gid) != 1)
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root_gid = va.va_gid;
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if (mp->mnt_cred->cr_ruid != 0 ||
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vfs_scanopt(mp->mnt_optnew, "uid", "%d", &root_uid) != 1)
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root_uid = va.va_uid;
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if (mp->mnt_cred->cr_ruid != 0 ||
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vfs_scanopt(mp->mnt_optnew, "mode", "%ho", &root_mode) != 1)
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root_mode = va.va_mode;
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if (vfs_getopt_size(mp->mnt_optnew, "inodes", &nodes_max) != 0)
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nodes_max = 0;
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if (vfs_getopt_size(mp->mnt_optnew, "size", &size_max) != 0)
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size_max = 0;
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if (vfs_getopt_size(mp->mnt_optnew, "maxfilesize", &maxfilesize) != 0)
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maxfilesize = 0;
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if (vfs_getopt_size(mp->mnt_optnew, "easize", &ea_max_size) != 0)
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ea_max_size = 0;
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nonc = vfs_getopt(mp->mnt_optnew, "nonc", NULL, NULL) == 0;
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nomtime = vfs_getopt(mp->mnt_optnew, "nomtime", NULL, NULL) == 0;
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pgread = vfs_getopt(mp->mnt_optnew, "pgread", NULL, NULL) == 0;
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/* Do not allow mounts if we do not have enough memory to preserve
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* the minimum reserved pages. */
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if (tmpfs_mem_avail() < TMPFS_PAGES_MINRESERVED)
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return (ENOSPC);
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/* Get the maximum number of memory pages this file system is
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* allowed to use, based on the maximum size the user passed in
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* the mount structure. A value of zero is treated as if the
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* maximum available space was requested. */
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if (size_max == 0 || size_max > OFF_MAX - PAGE_SIZE ||
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(SIZE_MAX < OFF_MAX && size_max / PAGE_SIZE >= SIZE_MAX))
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pages = SIZE_MAX;
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else {
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size_max = roundup(size_max, PAGE_SIZE);
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pages = howmany(size_max, PAGE_SIZE);
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}
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MPASS(pages > 0);
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if (nodes_max <= 3) {
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if (pages < INT_MAX / nodes_per_page)
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nodes_max = pages * nodes_per_page;
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else
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nodes_max = INT_MAX;
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}
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if (nodes_max > INT_MAX)
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nodes_max = INT_MAX;
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MPASS(nodes_max >= 3);
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/* Allocate the tmpfs mount structure and fill it. */
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tmp = (struct tmpfs_mount *)malloc(sizeof(struct tmpfs_mount),
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M_TMPFSMNT, M_WAITOK | M_ZERO);
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mtx_init(&tmp->tm_allnode_lock, "tmpfs allnode lock", NULL, MTX_DEF);
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tmp->tm_nodes_max = nodes_max;
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tmp->tm_nodes_inuse = 0;
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tmp->tm_ea_memory_inuse = 0;
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tmp->tm_refcount = 1;
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tmp->tm_maxfilesize = maxfilesize > 0 ? maxfilesize : OFF_MAX;
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tmp->tm_ea_memory_max = ea_max_size > 0 ?
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ea_max_size : TMPFS_EA_MEMORY_RESERVED;
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LIST_INIT(&tmp->tm_nodes_used);
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tmp->tm_size_max = size_max;
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tmp->tm_pages_max = pages;
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tmp->tm_pages_used = 0;
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new_unrhdr64(&tmp->tm_ino_unr, 2);
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tmp->tm_ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
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tmp->tm_nonc = nonc;
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tmp->tm_nomtime = nomtime;
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tmp->tm_pgread = pgread;
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/* Allocate the root node. */
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error = tmpfs_alloc_node(mp, tmp, VDIR, root_uid, root_gid,
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root_mode & ALLPERMS, NULL, NULL, VNOVAL, &root);
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if (error != 0 || root == NULL) {
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free(tmp, M_TMPFSMNT);
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return (error);
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}
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KASSERT(root->tn_id == 2,
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("tmpfs root with invalid ino: %ju", (uintmax_t)root->tn_id));
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tmp->tm_root = root;
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MNT_ILOCK(mp);
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mp->mnt_flag |= MNT_LOCAL;
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mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED |
|
|
MNTK_NOMSYNC;
|
|
if (!nonc && (mp->mnt_flag & MNT_UNION) == 0)
|
|
mp->mnt_kern_flag |= MNTK_FPLOOKUP;
|
|
MNT_IUNLOCK(mp);
|
|
|
|
mp->mnt_data = tmp;
|
|
mp->mnt_stat.f_namemax = MAXNAMLEN;
|
|
vfs_getnewfsid(mp);
|
|
vfs_mountedfrom(mp, "tmpfs");
|
|
|
|
return (0);
|
|
}
|
|
|
|
/* ARGSUSED2 */
|
|
static int
|
|
tmpfs_unmount(struct mount *mp, int mntflags)
|
|
{
|
|
struct tmpfs_mount *tmp;
|
|
struct tmpfs_node *node;
|
|
int error, flags;
|
|
|
|
flags = (mntflags & MNT_FORCE) != 0 ? FORCECLOSE : 0;
|
|
tmp = VFS_TO_TMPFS(mp);
|
|
|
|
/* Stop writers */
|
|
error = vfs_write_suspend_umnt(mp);
|
|
if (error != 0)
|
|
return (error);
|
|
/*
|
|
* At this point, nodes cannot be destroyed by any other
|
|
* thread because write suspension is started.
|
|
*/
|
|
|
|
for (;;) {
|
|
error = vflush(mp, 0, flags, curthread);
|
|
if (error != 0) {
|
|
vfs_write_resume(mp, VR_START_WRITE);
|
|
return (error);
|
|
}
|
|
MNT_ILOCK(mp);
|
|
if (mp->mnt_nvnodelistsize == 0) {
|
|
MNT_IUNLOCK(mp);
|
|
break;
|
|
}
|
|
MNT_IUNLOCK(mp);
|
|
if ((mntflags & MNT_FORCE) == 0) {
|
|
vfs_write_resume(mp, VR_START_WRITE);
|
|
return (EBUSY);
|
|
}
|
|
}
|
|
|
|
TMPFS_LOCK(tmp);
|
|
while ((node = LIST_FIRST(&tmp->tm_nodes_used)) != NULL) {
|
|
TMPFS_NODE_LOCK(node);
|
|
if (node->tn_type == VDIR)
|
|
tmpfs_dir_destroy(tmp, node);
|
|
if (tmpfs_free_node_locked(tmp, node, true))
|
|
TMPFS_LOCK(tmp);
|
|
else
|
|
TMPFS_NODE_UNLOCK(node);
|
|
}
|
|
|
|
mp->mnt_data = NULL;
|
|
tmpfs_free_tmp(tmp);
|
|
vfs_write_resume(mp, VR_START_WRITE);
|
|
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
tmpfs_free_tmp(struct tmpfs_mount *tmp)
|
|
{
|
|
TMPFS_MP_ASSERT_LOCKED(tmp);
|
|
MPASS(tmp->tm_refcount > 0);
|
|
|
|
tmp->tm_refcount--;
|
|
if (tmp->tm_refcount > 0) {
|
|
TMPFS_UNLOCK(tmp);
|
|
return;
|
|
}
|
|
TMPFS_UNLOCK(tmp);
|
|
|
|
mtx_destroy(&tmp->tm_allnode_lock);
|
|
/*
|
|
* We cannot assert that tmp->tm_pages_used == 0 there,
|
|
* because tmpfs vm_objects might be still mapped by some
|
|
* process and outlive the mount due to reference counting.
|
|
*/
|
|
MPASS(tmp->tm_nodes_inuse == 0);
|
|
|
|
free(tmp, M_TMPFSMNT);
|
|
}
|
|
|
|
static int
|
|
tmpfs_root(struct mount *mp, int flags, struct vnode **vpp)
|
|
{
|
|
int error;
|
|
|
|
error = tmpfs_alloc_vp(mp, VFS_TO_TMPFS(mp)->tm_root, flags, vpp);
|
|
if (error == 0)
|
|
(*vpp)->v_vflag |= VV_ROOT;
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
tmpfs_fhtovp(struct mount *mp, struct fid *fhp, int flags,
|
|
struct vnode **vpp)
|
|
{
|
|
struct tmpfs_fid_data tfd;
|
|
struct tmpfs_mount *tmp;
|
|
struct tmpfs_node *node;
|
|
int error;
|
|
|
|
if (fhp->fid_len != sizeof(tfd))
|
|
return (EINVAL);
|
|
|
|
/*
|
|
* Copy from fid_data onto the stack to avoid unaligned pointer use.
|
|
* See the comment in sys/mount.h on struct fid for details.
|
|
*/
|
|
memcpy(&tfd, fhp->fid_data, fhp->fid_len);
|
|
|
|
tmp = VFS_TO_TMPFS(mp);
|
|
|
|
if (tfd.tfd_id >= tmp->tm_nodes_max)
|
|
return (EINVAL);
|
|
|
|
TMPFS_LOCK(tmp);
|
|
LIST_FOREACH(node, &tmp->tm_nodes_used, tn_entries) {
|
|
if (node->tn_id == tfd.tfd_id &&
|
|
node->tn_gen == tfd.tfd_gen) {
|
|
tmpfs_ref_node(node);
|
|
break;
|
|
}
|
|
}
|
|
TMPFS_UNLOCK(tmp);
|
|
|
|
if (node != NULL) {
|
|
error = tmpfs_alloc_vp(mp, node, LK_EXCLUSIVE, vpp);
|
|
tmpfs_free_node(tmp, node);
|
|
} else
|
|
error = EINVAL;
|
|
return (error);
|
|
}
|
|
|
|
/* ARGSUSED2 */
|
|
static int
|
|
tmpfs_statfs(struct mount *mp, struct statfs *sbp)
|
|
{
|
|
struct tmpfs_mount *tmp;
|
|
size_t used;
|
|
|
|
tmp = VFS_TO_TMPFS(mp);
|
|
|
|
sbp->f_iosize = PAGE_SIZE;
|
|
sbp->f_bsize = PAGE_SIZE;
|
|
|
|
used = tmpfs_pages_used(tmp);
|
|
if (tmp->tm_pages_max != ULONG_MAX)
|
|
sbp->f_blocks = tmp->tm_pages_max;
|
|
else
|
|
sbp->f_blocks = used + tmpfs_mem_avail();
|
|
if (sbp->f_blocks <= used)
|
|
sbp->f_bavail = 0;
|
|
else
|
|
sbp->f_bavail = sbp->f_blocks - used;
|
|
sbp->f_bfree = sbp->f_bavail;
|
|
used = tmp->tm_nodes_inuse;
|
|
sbp->f_files = tmp->tm_nodes_max;
|
|
if (sbp->f_files <= used)
|
|
sbp->f_ffree = 0;
|
|
else
|
|
sbp->f_ffree = sbp->f_files - used;
|
|
/* sbp->f_owner = tmp->tn_uid; */
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
tmpfs_sync(struct mount *mp, int waitfor)
|
|
{
|
|
|
|
if (waitfor == MNT_SUSPEND) {
|
|
MNT_ILOCK(mp);
|
|
mp->mnt_kern_flag |= MNTK_SUSPEND2 | MNTK_SUSPENDED;
|
|
MNT_IUNLOCK(mp);
|
|
} else if (waitfor == MNT_LAZY) {
|
|
tmpfs_update_mtime_lazy(mp);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
tmpfs_init(struct vfsconf *conf)
|
|
{
|
|
int res;
|
|
|
|
res = tmpfs_subr_init();
|
|
if (res != 0)
|
|
return (res);
|
|
memcpy(&tmpfs_fnops, &vnops, sizeof(struct fileops));
|
|
tmpfs_fnops.fo_close = tmpfs_fo_close;
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
tmpfs_uninit(struct vfsconf *conf)
|
|
{
|
|
tmpfs_subr_uninit();
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* tmpfs vfs operations.
|
|
*/
|
|
struct vfsops tmpfs_vfsops = {
|
|
.vfs_mount = tmpfs_mount,
|
|
.vfs_unmount = tmpfs_unmount,
|
|
.vfs_root = vfs_cache_root,
|
|
.vfs_cachedroot = tmpfs_root,
|
|
.vfs_statfs = tmpfs_statfs,
|
|
.vfs_fhtovp = tmpfs_fhtovp,
|
|
.vfs_sync = tmpfs_sync,
|
|
.vfs_init = tmpfs_init,
|
|
.vfs_uninit = tmpfs_uninit,
|
|
};
|
|
VFS_SET(tmpfs_vfsops, tmpfs, VFCF_JAIL);
|
|
|
|
#ifdef DDB
|
|
#include <ddb/ddb.h>
|
|
|
|
static void
|
|
db_print_tmpfs(struct mount *mp, struct tmpfs_mount *tmp)
|
|
{
|
|
db_printf("mp %p (%s) tmp %p\n", mp,
|
|
mp->mnt_stat.f_mntonname, tmp);
|
|
db_printf(
|
|
"\tsize max %ju pages max %lu pages used %lu\n"
|
|
"\tinodes max %ju inodes inuse %ju ea inuse %ju refcount %ju\n"
|
|
"\tmaxfilesize %ju r%c %snamecache %smtime\n",
|
|
(uintmax_t)tmp->tm_size_max, tmp->tm_pages_max, tmp->tm_pages_used,
|
|
(uintmax_t)tmp->tm_nodes_max, (uintmax_t)tmp->tm_nodes_inuse,
|
|
(uintmax_t)tmp->tm_ea_memory_inuse, (uintmax_t)tmp->tm_refcount,
|
|
(uintmax_t)tmp->tm_maxfilesize,
|
|
tmp->tm_ronly ? 'o' : 'w', tmp->tm_nonc ? "no" : "",
|
|
tmp->tm_nomtime ? "no" : "");
|
|
}
|
|
|
|
DB_SHOW_COMMAND(tmpfs, db_show_tmpfs)
|
|
{
|
|
struct mount *mp;
|
|
struct tmpfs_mount *tmp;
|
|
|
|
if (have_addr) {
|
|
mp = (struct mount *)addr;
|
|
tmp = VFS_TO_TMPFS(mp);
|
|
db_print_tmpfs(mp, tmp);
|
|
return;
|
|
}
|
|
|
|
TAILQ_FOREACH(mp, &mountlist, mnt_list) {
|
|
if (strcmp(mp->mnt_stat.f_fstypename, tmpfs_vfsconf.vfc_name) ==
|
|
0) {
|
|
tmp = VFS_TO_TMPFS(mp);
|
|
db_print_tmpfs(mp, tmp);
|
|
}
|
|
}
|
|
}
|
|
#endif /* DDB */
|